Ok I guess I have to make 2 top 5 : the well-known ones and the others.

1. Macross Frontier
2. Death Note
3. Code Geass Hangyaku no Lelouchhhhhhhh
4. Gundam Seed / 00
5. Tengen Toppa Gurren Lagann

Honorable mention : Ghost in the Shell.

1. Gankutsuou (The Count of Monte-Cristo)
2. Mushishi
3. Eureka Seven
4. Mai-Hime
5. Speed Grapher

Honorable mention : Jyu-Oh-Sei

My top 5 as i ranked on MAL (all with 10..the only with 10)
1 Sword Art Online & Sword Art Online II
2 Golden Time
3 Shigatsu wa Kimi no Uso
4 Plastic Memories
5 Charlotte

My top 5
1. The file of young Kindaichi
2. Sket dance
3. Charlotte
4. Naruto
5. The seven deadly sins

i dont watch many anime.. 
but i read many manga..
some of the anime i watch and my favourite xD

1. one piece
2. death note
3. full metal alchemist(didnt watch brotherhood yet lol)
4. naruto
5. no game no life

mine has changed, so it now looks like this:

1. Naruto
2. Hunter x Hunter
3. Fate Stay Night: Unlimited Blade Works
4. Kimi ni Todoke
5. Fate Zero